Axon-Carrying Dendrites

Visualizations of likely axon-carrying dendrites in the Layer 2/3 serial EM volume


Summary Presentation

View the summary presentation file: axon_carrying_dendrite_presentation.pdf


Visualizations

Case 1

View in neuroglancer.


This reconstruction was made using the synapse_visualizer.ipynb notebook. The post-synaptic sites (on the dendrites) are shown in red and the pre-synaptic sites (on the presumtive axon) are shown in green for cellid 648518346349536971.

Pre- and post-synaptic sites on the axonal and dendritic processes for cellid 648518346349536971


Raw Electron Micrographs show it is likely not a segmentation error

Review of the raw EM images, the presumptive axonal process is continuous with the dendrite and does not appear to be a segmentation error.

EM view of axon-carrying dendrite for cellid 648518346349536971


Case 2

View in Neuroglancer

This is another potential axon-carrying dendrite for cellid 648518346349536971. This is likely an L5 or L6 pyramidal neuron from a deeper layer below the Layer 2/3 volume.

Pre- and post-synaptic sites on the axonal and dendritic processes for cellid 648518346342793912


Raw Electron Micrographs show it is likely not a segmentation error

Review of the raw EM images, the presumptive axonal process is continuous with the dendrite and does not appear to be a segmentation error.

EM view of axon-carrying dendrite for cellid 648518346342793912


Case 3

View in Neuroglancer.

3D reconstruction of bipolar inhibitory neuron withaxon-carrying dendrite. Pre-synaptic sites shown in green and post-synaptic sites shown in red.

3D reconstruction of bipolar inhibitory neuron withaxon-carrying dendrite.


Neuroglancer view of bipolar neuron with an axon-carrying dendrite.

Neuroglancer view of bipolar neuron with an axon-carrying dendrite


Case 4

View in Neuroglancer.

Dendrite from an excitatory pyramidal neuron (cell body is not within the Layer 2/3 volume) that has an axon-carrying dendrite within the volume.

3D view of axon-carrying dendrite on cell segment id 648518346341413916


Raw Electron Micrographs show it is likely not a segmentation error

Review of the raw EM images, the presumptive axonal process is continuous with the dendrite and does not appear to be a segmentation error.

Neuroglancer four-panel view of axon-carrying dendrite for cell segmentation id 648518346341413916


Wahle et al, ELife 2022

Axon-carrying dendrites (AcD) are not uncommon in rodents, with estimated 10-21% of pyramidal neurons having AcDs. See their paper in eLife entitled Neocortical pyramidal neurons with axons emerging from dendrites are frequent in non-primates, but rare in monkey and human for more details.